arch/parisc/include/asm/pgtable.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef _PARISC_PGTABLE_H
   3 #define _PARISC_PGTABLE_H
   4
   5 #include <asm/page.h>
   6
   7 #if CONFIG_PGTABLE_LEVELS == 3
   8 #include <asm-generic/pgtable-nopud.h>
   9 #elif CONFIG_PGTABLE_LEVELS == 2
  10 #include <asm-generic/pgtable-nopmd.h>
  11 #endif
  12
  13 #include <asm/fixmap.h>
  14
  15 #ifndef __ASSEMBLY__
  16 /*
  17  * we simulate an x86-style page table for the linux mm code
  18  */
  19
  20 #include <linux/bitops.h>
  21 #include <linux/spinlock.h>
  22 #include <linux/mm_types.h>
  23 #include <asm/processor.h>
  24 #include <asm/cache.h>
  25
  26 static inline spinlock_t *pgd_spinlock(pgd_t *);
  27
  28 /*
  29  * kern_addr_valid(ADDR) tests if ADDR is pointing to valid kernel
  30  * memory.  For the return value to be meaningful, ADDR must be >=
  31  * PAGE_OFFSET.  This operation can be relatively expensive (e.g.,
  32  * require a hash-, or multi-level tree-lookup or something of that
  33  * sort) but it guarantees to return TRUE only if accessing the page
  34  * at that address does not cause an error.  Note that there may be
  35  * addresses for which kern_addr_valid() returns FALSE even though an
  36  * access would not cause an error (e.g., this is typically true for
  37  * memory mapped I/O regions.
  38  *
  39  * XXX Need to implement this for parisc.
  40  */
  41 #define kern_addr_valid(addr)   (1)
  42
  43 /* This is for the serialization of PxTLB broadcasts. At least on the N class
  44  * systems, only one PxTLB inter processor broadcast can be active at any one
  45  * time on the Merced bus.
  46
  47  * PTE updates are protected by locks in the PMD.
  48  */
  49 extern spinlock_t pa_tlb_flush_lock;
  50 extern spinlock_t pa_swapper_pg_lock;
  51 #if defined(CONFIG_64BIT) && defined(CONFIG_SMP)
  52 extern int pa_serialize_tlb_flushes;
  53 #else
  54 #define pa_serialize_tlb_flushes        (0)
  55 #endif
  56
  57 #define purge_tlb_start(flags)  do { \
  58         if (pa_serialize_tlb_flushes)   \
  59                 spin_lock_irqsave(&pa_tlb_flush_lock, flags); \
  60         else \
  61                 local_irq_save(flags);  \
  62         } while (0)
  63 #define purge_tlb_end(flags)    do { \
  64         if (pa_serialize_tlb_flushes)   \
  65                 spin_unlock_irqrestore(&pa_tlb_flush_lock, flags); \
  66         else \
  67                 local_irq_restore(flags); \
  68         } while (0)
  69
  70 /* Purge data and instruction TLB entries. The TLB purge instructions
  71  * are slow on SMP machines since the purge must be broadcast to all CPUs.
  72  */
  73
  74 static inline void purge_tlb_entries(struct mm_struct *mm, unsigned long addr)
  75 {
  76         unsigned long flags;
  77
  78         purge_tlb_start(flags);
  79         mtsp(mm->context, 1);
  80         pdtlb(addr);
  81         pitlb(addr);
  82         purge_tlb_end(flags);
  83 }
  84
  85 /* Certain architectures need to do special things when PTEs
  86  * within a page table are directly modified.  Thus, the following
  87  * hook is made available.
  88  */
  89 #define set_pte(pteptr, pteval)                                 \
  90         do{                                                     \
  91                 *(pteptr) = (pteval);                           \
  92         } while(0)
  93
  94 #define set_pte_at(mm, addr, ptep, pteval)                      \
  95         do {                                                    \
  96                 pte_t old_pte;                                  \
  97                 unsigned long flags;                            \
  98                 spin_lock_irqsave(pgd_spinlock((mm)->pgd), flags);\
  99                 old_pte = *ptep;                                \
 100                 set_pte(ptep, pteval);                          \
 101                 purge_tlb_entries(mm, addr);                    \
 102                 spin_unlock_irqrestore(pgd_spinlock((mm)->pgd), flags);\
 103         } while (0)
 104
 105 #endif /* !__ASSEMBLY__ */
 106
 107 #define pte_ERROR(e) \
 108         printk("%s:%d: bad pte %08lx.\n", __FILE__, __LINE__, pte_val(e))
 109 #if CONFIG_PGTABLE_LEVELS == 3
 110 #define pmd_ERROR(e) \
 111         printk("%s:%d: bad pmd %08lx.\n", __FILE__, __LINE__, (unsigned long)pmd_val(e))
 112 #endif
 113 #define pgd_ERROR(e) \
 114         printk("%s:%d: bad pgd %08lx.\n", __FILE__, __LINE__, (unsigned long)pgd_val(e))
 115
 116 /* This is the size of the initially mapped kernel memory */
 117 #if defined(CONFIG_64BIT)
 118 #define KERNEL_INITIAL_ORDER    26      /* 1<<26 = 64MB */
 119 #else
 120 #define KERNEL_INITIAL_ORDER    25      /* 1<<25 = 32MB */
 121 #endif
 122 #define KERNEL_INITIAL_SIZE     (1 << KERNEL_INITIAL_ORDER)
 123
 124 #if CONFIG_PGTABLE_LEVELS == 3
 125 #define PGD_ORDER       1 /* Number of pages per pgd */
 126 #define PMD_ORDER       1 /* Number of pages per pmd */
 127 #define PGD_ALLOC_ORDER (2 + 1) /* first pgd contains pmd */
 128 #else
 129 #define PGD_ORDER       1 /* Number of pages per pgd */
 130 #define PGD_ALLOC_ORDER (PGD_ORDER + 1)
 131 #endif
 132
 133 /* Definitions for 3rd level (we use PLD here for Page Lower directory
 134  * because PTE_SHIFT is used lower down to mean shift that has to be
 135  * done to get usable bits out of the PTE) */
 136 #define PLD_SHIFT       PAGE_SHIFT
 137 #define PLD_SIZE        PAGE_SIZE
 138 #define BITS_PER_PTE    (PAGE_SHIFT - BITS_PER_PTE_ENTRY)
 139 #define PTRS_PER_PTE    (1UL << BITS_PER_PTE)
 140
 141 /* Definitions for 2nd level */
 142 #if CONFIG_PGTABLE_LEVELS == 3
 143 #define PMD_SHIFT       (PLD_SHIFT + BITS_PER_PTE)
 144 #define PMD_SIZE        (1UL << PMD_SHIFT)
 145 #define PMD_MASK        (~(PMD_SIZE-1))
 146 #define BITS_PER_PMD    (PAGE_SHIFT + PMD_ORDER - BITS_PER_PMD_ENTRY)
 147 #define PTRS_PER_PMD    (1UL << BITS_PER_PMD)
 148 #else
 149 #define BITS_PER_PMD    0
 150 #endif
 151
 152 /* Definitions for 1st level */
 153 #define PGDIR_SHIFT     (PLD_SHIFT + BITS_PER_PTE + BITS_PER_PMD)
 154 #if (PGDIR_SHIFT + PAGE_SHIFT + PGD_ORDER - BITS_PER_PGD_ENTRY) > BITS_PER_LONG
 155 #define BITS_PER_PGD    (BITS_PER_LONG - PGDIR_SHIFT)
 156 #else
 157 #define BITS_PER_PGD    (PAGE_SHIFT + PGD_ORDER - BITS_PER_PGD_ENTRY)
 158 #endif
 159 #define PGDIR_SIZE      (1UL << PGDIR_SHIFT)
 160 #define PGDIR_MASK      (~(PGDIR_SIZE-1))
 161 #define PTRS_PER_PGD    (1UL << BITS_PER_PGD)
 162 #define USER_PTRS_PER_PGD       PTRS_PER_PGD
 163
 164 #ifdef CONFIG_64BIT
 165 #define MAX_ADDRBITS    (PGDIR_SHIFT + BITS_PER_PGD)
 166 #define MAX_ADDRESS     (1UL << MAX_ADDRBITS)
 167 #define SPACEID_SHIFT   (MAX_ADDRBITS - 32)
 168 #else
 169 #define MAX_ADDRBITS    (BITS_PER_LONG)
 170 #define MAX_ADDRESS     (1UL << MAX_ADDRBITS)
 171 #define SPACEID_SHIFT   0
 172 #endif
 173
 174 /* This calculates the number of initial pages we need for the initial
 175  * page tables */
 176 #if (KERNEL_INITIAL_ORDER) >= (PMD_SHIFT)
 177 # define PT_INITIAL     (1 << (KERNEL_INITIAL_ORDER - PMD_SHIFT))
 178 #else
 179 # define PT_INITIAL     (1)  /* all initial PTEs fit into one page */
 180 #endif
 181
 182 /*
 183  * pgd entries used up by user/kernel:
 184  */
 185
 186 #define FIRST_USER_ADDRESS      0UL
 187
 188 /* NB: The tlb miss handlers make certain assumptions about the order */
 189 /*     of the following bits, so be careful (One example, bits 25-31  */
 190 /*     are moved together in one instruction).                        */
 191
 192 #define _PAGE_READ_BIT     31   /* (0x001) read access allowed */
 193 #define _PAGE_WRITE_BIT    30   /* (0x002) write access allowed */
 194 #define _PAGE_EXEC_BIT     29   /* (0x004) execute access allowed */
 195 #define _PAGE_GATEWAY_BIT  28   /* (0x008) privilege promotion allowed */
 196 #define _PAGE_DMB_BIT      27   /* (0x010) Data Memory Break enable (B bit) */
 197 #define _PAGE_DIRTY_BIT    26   /* (0x020) Page Dirty (D bit) */
 198 #define _PAGE_REFTRAP_BIT  25   /* (0x040) Page Ref. Trap enable (T bit) */
 199 #define _PAGE_NO_CACHE_BIT 24   /* (0x080) Uncached Page (U bit) */
 200 #define _PAGE_ACCESSED_BIT 23   /* (0x100) Software: Page Accessed */
 201 #define _PAGE_PRESENT_BIT  22   /* (0x200) Software: translation valid */
 202 #define _PAGE_HPAGE_BIT    21   /* (0x400) Software: Huge Page */
 203 #define _PAGE_USER_BIT     20   /* (0x800) Software: User accessible page */
 204
 205 /* N.B. The bits are defined in terms of a 32 bit word above, so the */
 206 /*      following macro is ok for both 32 and 64 bit.                */
 207
 208 #define xlate_pabit(x) (31 - x)
 209
 210 /* this defines the shift to the usable bits in the PTE it is set so
 211  * that the valid bits _PAGE_PRESENT_BIT and _PAGE_USER_BIT are set
 212  * to zero */
 213 #define PTE_SHIFT               xlate_pabit(_PAGE_USER_BIT)
 214
 215 /* PFN_PTE_SHIFT defines the shift of a PTE value to access the PFN field */
 216 #define PFN_PTE_SHIFT           12
 217
 218 #define _PAGE_READ     (1 << xlate_pabit(_PAGE_READ_BIT))
 219 #define _PAGE_WRITE    (1 << xlate_pabit(_PAGE_WRITE_BIT))
 220 #define _PAGE_RW       (_PAGE_READ | _PAGE_WRITE)
 221 #define _PAGE_EXEC     (1 << xlate_pabit(_PAGE_EXEC_BIT))
 222 #define _PAGE_GATEWAY  (1 << xlate_pabit(_PAGE_GATEWAY_BIT))
 223 #define _PAGE_DMB      (1 << xlate_pabit(_PAGE_DMB_BIT))
 224 #define _PAGE_DIRTY    (1 << xlate_pabit(_PAGE_DIRTY_BIT))
 225 #define _PAGE_REFTRAP  (1 << xlate_pabit(_PAGE_REFTRAP_BIT))
 226 #define _PAGE_NO_CACHE (1 << xlate_pabit(_PAGE_NO_CACHE_BIT))
 227 #define _PAGE_ACCESSED (1 << xlate_pabit(_PAGE_ACCESSED_BIT))
 228 #define _PAGE_PRESENT  (1 << xlate_pabit(_PAGE_PRESENT_BIT))
 229 #define _PAGE_HUGE     (1 << xlate_pabit(_PAGE_HPAGE_BIT))
 230 #define _PAGE_USER     (1 << xlate_pabit(_PAGE_USER_BIT))
 231
 232 #define _PAGE_TABLE     (_PAGE_PRESENT | _PAGE_READ | _PAGE_WRITE | _PAGE_DIRTY | _PAGE_ACCESSED)
 233 #define _PAGE_CHG_MASK  (PAGE_MASK | _PAGE_ACCESSED | _PAGE_DIRTY)
 234 #define _PAGE_KERNEL_RO (_PAGE_PRESENT | _PAGE_READ | _PAGE_DIRTY | _PAGE_ACCESSED)
 235 #define _PAGE_KERNEL_EXEC       (_PAGE_KERNEL_RO | _PAGE_EXEC)
 236 #define _PAGE_KERNEL_RWX        (_PAGE_KERNEL_EXEC | _PAGE_WRITE)
 237 #define _PAGE_KERNEL            (_PAGE_KERNEL_RO | _PAGE_WRITE)
 238
 239 /* The pgd/pmd contains a ptr (in phys addr space); since all pgds/pmds
 240  * are page-aligned, we don't care about the PAGE_OFFSET bits, except
 241  * for a few meta-information bits, so we shift the address to be
 242  * able to effectively address 40/42/44-bits of physical address space
 243  * depending on 4k/16k/64k PAGE_SIZE */
 244 #define _PxD_PRESENT_BIT   31
 245 #define _PxD_ATTACHED_BIT  30
 246 #define _PxD_VALID_BIT     29
 247
 248 #define PxD_FLAG_PRESENT  (1 << xlate_pabit(_PxD_PRESENT_BIT))
 249 #define PxD_FLAG_ATTACHED (1 << xlate_pabit(_PxD_ATTACHED_BIT))
 250 #define PxD_FLAG_VALID    (1 << xlate_pabit(_PxD_VALID_BIT))
 251 #define PxD_FLAG_MASK     (0xf)
 252 #define PxD_FLAG_SHIFT    (4)
 253 #define PxD_VALUE_SHIFT   (PFN_PTE_SHIFT-PxD_FLAG_SHIFT)
 254
 255 #ifndef __ASSEMBLY__
 256
 257 #define PAGE_NONE       __pgprot(_PAGE_PRESENT | _PAGE_USER)
 258 #define PAGE_SHARED     __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_READ | _PAGE_WRITE)
 259 /* Others seem to make this executable, I don't know if that's correct
 260    or not.  The stack is mapped this way though so this is necessary
 261    in the short term - dhd@linuxcare.com, 2000-08-08 */
 262 #define PAGE_READONLY   __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_READ)
 263 #define PAGE_WRITEONLY  __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_WRITE)
 264 #define PAGE_EXECREAD   __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_READ | _PAGE_EXEC)
 265 #define PAGE_COPY       PAGE_EXECREAD
 266 #define PAGE_RWX        __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_READ | _PAGE_WRITE | _PAGE_EXEC)
 267 #define PAGE_KERNEL     __pgprot(_PAGE_KERNEL)
 268 #define PAGE_KERNEL_EXEC        __pgprot(_PAGE_KERNEL_EXEC)
 269 #define PAGE_KERNEL_RWX __pgprot(_PAGE_KERNEL_RWX)
 270 #define PAGE_KERNEL_RO  __pgprot(_PAGE_KERNEL_RO)
 271 #define PAGE_KERNEL_UNC __pgprot(_PAGE_KERNEL | _PAGE_NO_CACHE)
 272 #define PAGE_GATEWAY    __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_GATEWAY| _PAGE_READ)
 273
 274
 275 /*
 276  * We could have an execute only page using "gateway - promote to priv
 277  * level 3", but that is kind of silly. So, the way things are defined
 278  * now, we must always have read permission for pages with execute
 279  * permission. For the fun of it we'll go ahead and support write only
 280  * pages.
 281  */
 282
 283          /*xwr*/
 284 #define __P000  PAGE_NONE
 285 #define __P001  PAGE_READONLY
 286 #define __P010  __P000 /* copy on write */
 287 #define __P011  __P001 /* copy on write */
 288 #define __P100  PAGE_EXECREAD
 289 #define __P101  PAGE_EXECREAD
 290 #define __P110  __P100 /* copy on write */
 291 #define __P111  __P101 /* copy on write */
 292
 293 #define __S000  PAGE_NONE
 294 #define __S001  PAGE_READONLY
 295 #define __S010  PAGE_WRITEONLY
 296 #define __S011  PAGE_SHARED
 297 #define __S100  PAGE_EXECREAD
 298 #define __S101  PAGE_EXECREAD
 299 #define __S110  PAGE_RWX
 300 #define __S111  PAGE_RWX
 301
 302
 303 extern pgd_t swapper_pg_dir[]; /* declared in init_task.c */
 304
 305 /* initial page tables for 0-8MB for kernel */
 306
 307 extern pte_t pg0[];
 308
 309 /* zero page used for uninitialized stuff */
 310
 311 extern unsigned long *empty_zero_page;
 312
 313 /*
 314  * ZERO_PAGE is a global shared page that is always zero: used
 315  * for zero-mapped memory areas etc..
 316  */
 317
 318 #define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))
 319
 320 #define pte_none(x)     (pte_val(x) == 0)
 321 #define pte_present(x)  (pte_val(x) & _PAGE_PRESENT)
 322 #define pte_clear(mm, addr, xp)  set_pte_at(mm, addr, xp, __pte(0))
 323
 324 #define pmd_flag(x)     (pmd_val(x) & PxD_FLAG_MASK)
 325 #define pmd_address(x)  ((unsigned long)(pmd_val(x) &~ PxD_FLAG_MASK) << PxD_VALUE_SHIFT)
 326 #define pud_flag(x)     (pud_val(x) & PxD_FLAG_MASK)
 327 #define pud_address(x)  ((unsigned long)(pud_val(x) &~ PxD_FLAG_MASK) << PxD_VALUE_SHIFT)
 328 #define pgd_flag(x)     (pgd_val(x) & PxD_FLAG_MASK)
 329 #define pgd_address(x)  ((unsigned long)(pgd_val(x) &~ PxD_FLAG_MASK) << PxD_VALUE_SHIFT)
 330
 331 #if CONFIG_PGTABLE_LEVELS == 3
 332 /* The first entry of the permanent pmd is not there if it contains
 333  * the gateway marker */
 334 #define pmd_none(x)     (!pmd_val(x) || pmd_flag(x) == PxD_FLAG_ATTACHED)
 335 #else
 336 #define pmd_none(x)     (!pmd_val(x))
 337 #endif
 338 #define pmd_bad(x)      (!(pmd_flag(x) & PxD_FLAG_VALID))
 339 #define pmd_present(x)  (pmd_flag(x) & PxD_FLAG_PRESENT)
 340 static inline void pmd_clear(pmd_t *pmd) {
 341 #if CONFIG_PGTABLE_LEVELS == 3
 342         if (pmd_flag(*pmd) & PxD_FLAG_ATTACHED)
 343                 /* This is the entry pointing to the permanent pmd
 344                  * attached to the pgd; cannot clear it */
 345                 set_pmd(pmd, __pmd(PxD_FLAG_ATTACHED));
 346         else
 347 #endif
 348                 set_pmd(pmd,  __pmd(0));
 349 }
 350
 351
 352
 353 #if CONFIG_PGTABLE_LEVELS == 3
 354 #define pud_page_vaddr(pud) ((unsigned long) __va(pud_address(pud)))
 355 #define pud_page(pud)   virt_to_page((void *)pud_page_vaddr(pud))
 356
 357 /* For 64 bit we have three level tables */
 358
 359 #define pud_none(x)     (!pud_val(x))
 360 #define pud_bad(x)      (!(pud_flag(x) & PxD_FLAG_VALID))
 361 #define pud_present(x)  (pud_flag(x) & PxD_FLAG_PRESENT)
 362 static inline void pud_clear(pud_t *pud) {
 363 #if CONFIG_PGTABLE_LEVELS == 3
 364         if(pud_flag(*pud) & PxD_FLAG_ATTACHED)
 365                 /* This is the permanent pmd attached to the pud; cannot
 366                  * free it */
 367                 return;
 368 #endif
 369         set_pud(pud, __pud(0));
 370 }
 371 #endif
 372
 373 /*
 374  * The following only work if pte_present() is true.
 375  * Undefined behaviour if not..
 376  */
 377 static inline int pte_dirty(pte_t pte)          { return pte_val(pte) & _PAGE_DIRTY; }
 378 static inline int pte_young(pte_t pte)          { return pte_val(pte) & _PAGE_ACCESSED; }
 379 static inline int pte_write(pte_t pte)          { return pte_val(pte) & _PAGE_WRITE; }
 380
 381 static inline pte_t pte_mkclean(pte_t pte)      { pte_val(pte) &= ~_PAGE_DIRTY; return pte; }
 382 static inline pte_t pte_mkold(pte_t pte)        { pte_val(pte) &= ~_PAGE_ACCESSED; return pte; }
 383 static inline pte_t pte_wrprotect(pte_t pte)    { pte_val(pte) &= ~_PAGE_WRITE; return pte; }
 384 static inline pte_t pte_mkdirty(pte_t pte)      { pte_val(pte) |= _PAGE_DIRTY; return pte; }
 385 static inline pte_t pte_mkyoung(pte_t pte)      { pte_val(pte) |= _PAGE_ACCESSED; return pte; }
 386 static inline pte_t pte_mkwrite(pte_t pte)      { pte_val(pte) |= _PAGE_WRITE; return pte; }
 387
 388 /*
 389  * Huge pte definitions.
 390  */
 391 #ifdef CONFIG_HUGETLB_PAGE
 392 #define pte_huge(pte)           (pte_val(pte) & _PAGE_HUGE)
 393 #define pte_mkhuge(pte)         (__pte(pte_val(pte) | \
 394                                  (parisc_requires_coherency() ? 0 : _PAGE_HUGE)))
 395 #else
 396 #define pte_huge(pte)           (0)
 397 #define pte_mkhuge(pte)         (pte)
 398 #endif
 399
 400
 401 /*
 402  * Conversion functions: convert a page and protection to a page entry,
 403  * and a page entry and page directory to the page they refer to.
 404  */
 405 #define __mk_pte(addr,pgprot) \
 406 ({                                                                      \
 407         pte_t __pte;                                                    \
 408                                                                         \
 409         pte_val(__pte) = ((((addr)>>PAGE_SHIFT)<<PFN_PTE_SHIFT) + pgprot_val(pgprot));  \
 410                                                                         \
 411         __pte;                                                          \
 412 })
 413
 414 #define mk_pte(page, pgprot)    pfn_pte(page_to_pfn(page), (pgprot))
 415
 416 static inline pte_t pfn_pte(unsigned long pfn, pgprot_t pgprot)
 417 {
 418         pte_t pte;
 419         pte_val(pte) = (pfn << PFN_PTE_SHIFT) | pgprot_val(pgprot);
 420         return pte;
 421 }
 422
 423 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
 424 { pte_val(pte) = (pte_val(pte) & _PAGE_CHG_MASK) | pgprot_val(newprot); return pte; }
 425
 426 /* Permanent address of a page.  On parisc we don't have highmem. */
 427
 428 #define pte_pfn(x)              (pte_val(x) >> PFN_PTE_SHIFT)
 429
 430 #define pte_page(pte)           (pfn_to_page(pte_pfn(pte)))
 431
 432 #define pmd_page_vaddr(pmd)     ((unsigned long) __va(pmd_address(pmd)))
 433
 434 #define __pmd_page(pmd) ((unsigned long) __va(pmd_address(pmd)))
 435 #define pmd_page(pmd)   virt_to_page((void *)__pmd_page(pmd))
 436
 437 #define pgd_index(address) ((address) >> PGDIR_SHIFT)
 438
 439 /* to find an entry in a page-table-directory */
 440 #define pgd_offset(mm, address) \
 441 ((mm)->pgd + ((address) >> PGDIR_SHIFT))
 442
 443 /* to find an entry in a kernel page-table-directory */
 444 #define pgd_offset_k(address) pgd_offset(&init_mm, address)
 445
 446 /* Find an entry in the second-level page table.. */
 447
 448 #if CONFIG_PGTABLE_LEVELS == 3
 449 #define pmd_index(addr)         (((addr) >> PMD_SHIFT) & (PTRS_PER_PMD - 1))
 450 #define pmd_offset(dir,address) \
 451 ((pmd_t *) pud_page_vaddr(*(dir)) + pmd_index(address))
 452 #else
 453 #define pmd_offset(dir,addr) ((pmd_t *) dir)
 454 #endif
 455
 456 /* Find an entry in the third-level page table.. */
 457 #define pte_index(address) (((address) >> PAGE_SHIFT) & (PTRS_PER_PTE-1))
 458 #define pte_offset_kernel(pmd, address) \
 459         ((pte_t *) pmd_page_vaddr(*(pmd)) + pte_index(address))
 460 #define pte_offset_map(pmd, address) pte_offset_kernel(pmd, address)
 461 #define pte_unmap(pte) do { } while (0)
 462
 463 #define pte_unmap(pte)                  do { } while (0)
 464 #define pte_unmap_nested(pte)           do { } while (0)
 465
 466 extern void paging_init (void);
 467
 468 /* Used for deferring calls to flush_dcache_page() */
 469
 470 #define PG_dcache_dirty         PG_arch_1
 471
 472 extern void update_mmu_cache(struct vm_area_struct *, unsigned long, pte_t *);
 473
 474 /* Encode and de-code a swap entry */
 475
 476 #define __swp_type(x)                     ((x).val & 0x1f)
 477 #define __swp_offset(x)                   ( (((x).val >> 6) &  0x7) | \
 478                                           (((x).val >> 8) & ~0x7) )
 479 #define __swp_entry(type, offset)         ((swp_entry_t) { (type) | \
 480                                             ((offset &  0x7) << 6) | \
 481                                             ((offset & ~0x7) << 8) })
 482 #define __pte_to_swp_entry(pte)         ((swp_entry_t) { pte_val(pte) })
 483 #define __swp_entry_to_pte(x)           ((pte_t) { (x).val })
 484
 485
 486 static inline spinlock_t *pgd_spinlock(pgd_t *pgd)
 487 {
 488         if (unlikely(pgd == swapper_pg_dir))
 489                 return &pa_swapper_pg_lock;
 490         return (spinlock_t *)((char *)pgd + (PAGE_SIZE << (PGD_ALLOC_ORDER - 1)));
 491 }
 492
 493
 494 static inline int ptep_test_and_clear_young(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep)
 495 {
 496         pte_t pte;
 497         unsigned long flags;
 498
 499         if (!pte_young(*ptep))
 500                 return 0;
 501
 502         spin_lock_irqsave(pgd_spinlock(vma->vm_mm->pgd), flags);
 503         pte = *ptep;
 504         if (!pte_young(pte)) {
 505                 spin_unlock_irqrestore(pgd_spinlock(vma->vm_mm->pgd), flags);
 506                 return 0;
 507         }
 508         set_pte(ptep, pte_mkold(pte));
 509         purge_tlb_entries(vma->vm_mm, addr);
 510         spin_unlock_irqrestore(pgd_spinlock(vma->vm_mm->pgd), flags);
 511         return 1;
 512 }
 513
 514 struct mm_struct;
 515 static inline pte_t ptep_get_and_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
 516 {
 517         pte_t old_pte;
 518         unsigned long flags;
 519
 520         spin_lock_irqsave(pgd_spinlock(mm->pgd), flags);
 521         old_pte = *ptep;
 522         set_pte(ptep, __pte(0));
 523         purge_tlb_entries(mm, addr);
 524         spin_unlock_irqrestore(pgd_spinlock(mm->pgd), flags);
 525
 526         return old_pte;
 527 }
 528
 529 static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
 530 {
 531         unsigned long flags;
 532         spin_lock_irqsave(pgd_spinlock(mm->pgd), flags);
 533         set_pte(ptep, pte_wrprotect(*ptep));
 534         purge_tlb_entries(mm, addr);
 535         spin_unlock_irqrestore(pgd_spinlock(mm->pgd), flags);
 536 }
 537
 538 #define pte_same(A,B)   (pte_val(A) == pte_val(B))
 539
 540 struct seq_file;
 541 extern void arch_report_meminfo(struct seq_file *m);
 542
 543 #endif /* !__ASSEMBLY__ */
 544
 545
 546 /* TLB page size encoding - see table 3-1 in parisc20.pdf */
 547 #define _PAGE_SIZE_ENCODING_4K          0
 548 #define _PAGE_SIZE_ENCODING_16K         1
 549 #define _PAGE_SIZE_ENCODING_64K         2
 550 #define _PAGE_SIZE_ENCODING_256K        3
 551 #define _PAGE_SIZE_ENCODING_1M          4
 552 #define _PAGE_SIZE_ENCODING_4M          5
 553 #define _PAGE_SIZE_ENCODING_16M         6
 554 #define _PAGE_SIZE_ENCODING_64M         7
 555
 556 #if defined(CONFIG_PARISC_PAGE_SIZE_4KB)
 557 # define _PAGE_SIZE_ENCODING_DEFAULT _PAGE_SIZE_ENCODING_4K
 558 #elif defined(CONFIG_PARISC_PAGE_SIZE_16KB)
 559 # define _PAGE_SIZE_ENCODING_DEFAULT _PAGE_SIZE_ENCODING_16K
 560 #elif defined(CONFIG_PARISC_PAGE_SIZE_64KB)
 561 # define _PAGE_SIZE_ENCODING_DEFAULT _PAGE_SIZE_ENCODING_64K
 562 #endif
 563
 564
 565 #define pgprot_noncached(prot) __pgprot(pgprot_val(prot) | _PAGE_NO_CACHE)
 566
 567 /* We provide our own get_unmapped_area to provide cache coherency */
 568
 569 #define HAVE_ARCH_UNMAPPED_AREA
 570 #define HAVE_ARCH_UNMAPPED_AREA_TOPDOWN
 571
 572 #define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
 573 #define __HAVE_ARCH_PTEP_GET_AND_CLEAR
 574 #define __HAVE_ARCH_PTEP_SET_WRPROTECT
 575 #define __HAVE_ARCH_PTE_SAME
 576 #include <asm-generic/pgtable.h>
 577
 578 #endif /* _PARISC_PGTABLE_H */